Institution
University of California, Santa Cruz
Education•Santa Cruz, California, United States•
About: University of California, Santa Cruz is a education organization based out in Santa Cruz, California, United States. It is known for research contribution in the topics: Galaxy & Population. The organization has 15541 authors who have published 44120 publications receiving 2759983 citations. The organization is also known as: UCSC & UC, Santa Cruz.
Topics: Galaxy, Population, Star formation, Redshift, Planet
Papers published on a yearly basis
Papers
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TL;DR: In this article, the authors derived the mass-loss rate, the entropy per baryon, the electron fraction, and the dynamic timescale of the neutrino-driven wind in supernovae.
Abstract: During the first 20 s of its life, the enormous neutrino luminosity of a neutron star drives appreciable mass loss from its surface. Previous investigations have shown that this neutrino-driven wind could be the site where the r-process occurs. The nucleosynthesis is sensitive to four physical parameters that characterize the wind: its mass-loss rate, the entropy per baryon, the electron fraction, and the dynamic timescale. Different authors, using numerical models for supernovae, have arrived at qualitatively different values for these key parameters. Here we derive their values analytically and test our analytic results by numerical calculations using an implicit hydrodynamic code. Employing our analytic and numerical methods, we also investigate how various factors can affect our results. The derived entropy typically falls short, by a factor of 2?3, of the value required to produce a strong r-process. Various factors that might give a higher entropy or a more rapid expansion in the wind are discussed.
586 citations
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TL;DR: The authors show that the annual damages from flooding would double globally without reefs and they quantify where reefs provide the most protection to people and property.
Abstract: Coral reefs can provide significant coastal protection benefits to people and property. Here we show that the annual expected damages from flooding would double, and costs from frequent storms would triple without reefs. For 100-year storm events, flood damages would increase by 91% to $US 272 billion without reefs. The countries with the most to gain from reef management are Indonesia, Philippines, Malaysia, Mexico, and Cuba; annual expected flood savings exceed $400 M for each of these nations. Sea-level rise will increase flood risk, but substantial impacts could happen from reef loss alone without better near-term management. We provide a global, process-based valuation of an ecosystem service across an entire marine biome at (sub)national levels. These spatially explicit benefits inform critical risk and environmental management decisions, and the expected benefits can be directly considered by governments (e.g., national accounts, recovery plans) and businesses (e.g., insurance). Coral reefs provide significant coastal protection from storms but they have experienced significant losses. Here the authors show that the annual damages from flooding would double globally without reefs and they quantify where reefs provide the most protection to people and property.
586 citations
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TL;DR: The detection of emission up to ∼31 GeV from the distant and short GRB, and no evidence for the violation of Lorentz invariance is found, which disfavour quantum-gravity theories in which the quantum nature of space–time on a very small scale linearly alters the speed of light.
Abstract: A cornerstone of Einstein's special relativity is Lorentz invariance-the postulate that all observers measure exactly the same speed of light in vacuum, independent of photon-energy. While special relativity assumes that there is no fundamental length-scale associated with such invariance, there is a fundamental scale (the Planck scale, l(Planck) approximate to 1.62 x 10(-33) cm or E(Planck) = M(Planck)c(2) approximate to 1.22 x 10(19) GeV), at which quantum effects are expected to strongly affect the nature of space-time. There is great interest in the (not yet validated) idea that Lorentz invariance might break near the Planck scale. A key test of such violation of Lorentz invariance is a possible variation of photon speed with energy(1-7). Even a tiny variation in photon speed, when accumulated over cosmological light-travel times, may be revealed by observing sharp features in gamma-ray burst (GRB) light-curves(2). Here we report the detection of emission up to similar to 31GeV from the distant and short GRB090510. We find no evidence for the violation of Lorentz invariance, and place a lower limit of 1.2E(Planck) on the scale of a linear energy dependence (or an inverse wavelength dependence), subject to reasonable assumptions about the emission (equivalently we have an upper limit of l(Planck)/1.2 on the length scale of the effect). Our results disfavour quantum-gravity theories(3,6,7) in which the quantum nature of space-time on a very small scale linearly alters the speed of light.
586 citations
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TL;DR: In this paper, the specification of evolutionary game models and the possible asymptotic behavior for one and two dimensional models are discussed. But the authors do not consider the problem of modeling substantive economic issues.
Abstract: Evolutionary games have considerable unrealized potential for modeling substantive economic issues. They promise richer predictions than orthodox game models but often require more extensive specifications. This paper exposits the specification of evolutionary game models and classifies the possible asymptotic behavior for one and two dimensional models.
585 citations
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TL;DR: Femtosecond laser surgery is used for axotomy in the roundworm Caenorhabditis elegans and it is shown that axons functionally regenerate after the operation.
Abstract: Understanding how nerves regenerate is an important step towards developing treatments for human neurological disease, but investigation has so far been limited to complex organisms (mouse and zebrafish) in the absence of precision techniques for severing axons (axotomy). Here we use femtosecond laser surgery for axotomy in the roundworm Caenorhabditis elegans and show that these axons functionally regenerate after the operation. Application of this precise surgical technique should enable nerve regeneration to be studied in vivo in its most evolutionarily simple form.
584 citations
Authors
Showing all 15733 results
Name | H-index | Papers | Citations |
---|---|---|---|
David J. Schlegel | 193 | 600 | 193972 |
David R. Williams | 178 | 2034 | 138789 |
John R. Yates | 177 | 1036 | 129029 |
David Haussler | 172 | 488 | 224960 |
Evan E. Eichler | 170 | 567 | 150409 |
Anton M. Koekemoer | 168 | 1127 | 106796 |
Mark Gerstein | 168 | 751 | 149578 |
Alexander S. Szalay | 166 | 936 | 145745 |
Charles M. Lieber | 165 | 521 | 132811 |
Jorge E. Cortes | 163 | 2784 | 124154 |
M. Razzano | 155 | 515 | 106357 |
Lars Hernquist | 148 | 598 | 88554 |
Aaron Dominguez | 147 | 1968 | 113224 |
Taeghwan Hyeon | 139 | 563 | 75814 |
Garth D. Illingworth | 137 | 505 | 61793 |